We propose to transition our membership status from the Biliary Atresia Research Consortium (BARC) and the Cholestatic Liver Consortium (CLiC) to the new Childhood Liver Disease Research and Education Network (ChiLDREN). Our proposal represents a logical extension of the long-standing commitment of our Center to improve the care of children with chronic liver disease through innovative patient-based research. We have been a charter member of BARC and CLiC since their creation in 2002 and 2004, respectively. We worked collaboratively with consortium investigators to build the infrastructure to conduct patient-based studies on biliary atresia and cholestatic syndromes. Our key contributions included data submission and analysis of two retrospective studies, leadership in the development of a clinical trial, high enrollment and retention of subjects into three prospective studies and one interventional study, completion of an ancillary study of novel molecular phenotypes of biliary atresia, completion of a pilot project on defects in bile acid synthesis, and participation in working groups and committees related to project reviews, writing of manuscripts, and development of core resources. We look forward to significantly contributing to the operation of ChiLDREN through three aims. In Aim 1, we will combine the expertise and resources of BARC and CLiC to form ChiLDREN. This will be done by transitioning the operation of ongoing study protocols to the working structure developed by the Steering Committee and the Data Coordinating Center, develop new study protocols, and continue to enroll subjects into approved studies. In Aim 2, we will promote specialty training, develop two core services (Bile Acid Biochemistry Core and Histopathology Core), and significantly expand access to study subjects by collaborating with investigators in the Hepatology and Liver Transplant Program at the Hospital for Sick Children, Toronto. And in Aim 3, we will use state-of-the-art molecular and cellular systems to study pathogenesis of liver disease and identify novel therapeutic targets for children with biliary atresia and cholestatic syndromes using data and tissue collected by ChiLDREN protocols. Relevance: We propose to become a member of the Childhood Liver Disease Research and Education Network and to contribute to the development of the infrastructure for clinical research in children with chronic liver disease. This infrastructure will facilitate innovative patient-based studies addressing etiology, pathogenesis, and clinical outcome of children with biliary atresia and inherited cholestatic syndromes.